Navalny, an anti-corruption blogger who is running for Moscow mayor, was detained late Sunday at an event for infringing "the rights and legal interests of other citizens," an unnamed police official told Interfax news agency.

Navalny was detained immediately after leaving the stage of a campaign event, and released a short time later. About 10 technicians who were working to dismantle the stage were also arrested, according to members of the Navalny campaign.

The detention, which appeared unprovoked, is part of a series of public signals to Navalny, who was given a verbal warning about various alleged campaign violations by the Moscow electoral committee last week.